What is this medicine?

METHENAMINE; SODIUM ACID PHOSPHATE; METHYLENE BLUE; HYOSCYAMINE (meth EN a meen; SOE dee um AS id FOS fate; METH uh leen bloo; hye oh SYE a meen) is used to stop the pain, burning, or discomfort caused by infection or irritation of the urinary tract. This medicine is not an antibiotic. It will not cure a urinary tract infection.

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take your medicine at regular intervals. Do not take it more often than directed. Do not stop taking except on your doctor's advice.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children at young as 6 years of age, precautions do apply.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:

allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue

blurred vision

breathing problems

dizziness

rapid pulse

trouble passing urine or change in the amount of urine

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

What should I watch for while using this medicine?

Tell your doctor or healthcare professional if your symptoms do not start to get better or if they get worse.

You may get drowsy or dizzy. Do not drive, use machinery, or do anything that needs mental alertness until you know how this medicine affects you. Do not stand or sit up quickly, especially if you are an older patient. This reduces the risk of dizzy or fainting spells.

Your mouth may get dry. Chewing sugarless gum or sucking hard candy, and drinking plenty of water may help. Contact your doctor if the problem does not go away or is severe.

You may need to be on a special diet while taking this medicine. Ask your health care professional how many glasses of water or other fluids to drink each day. Also, ask which foods to include and which to avoid to help keep your urine acidic. Your urine must be acidic for this medicine to work.

This medicine may cause dry eyes and blurred vision. If you wear contact lenses you may feel some discomfort. Lubricating drops may help. See your eye doctor if the problem does not go away or is severe.